package net.fortytwo.ripple.libs.control;
import net.fortytwo.flow.Sink;
import net.fortytwo.ripple.RippleException;
import net.fortytwo.ripple.model.ModelConnection;
import net.fortytwo.ripple.model.Operator;
import net.fortytwo.ripple.model.PrimitiveStackMapping;
import net.fortytwo.ripple.model.RippleList;
import net.fortytwo.ripple.model.RippleValue;
import net.fortytwo.ripple.model.StackMappingWrapper;
import net.fortytwo.ripple.model.regex.OptionalQuantifier;
/**
* A primitive which activates ("applies") the topmost item on the stack any
* number of times.
*
* @author Joshua Shinavier (http://fortytwo.net)
*/
public class OptionApply extends PrimitiveStackMapping {
private static final String[] IDENTIFIERS = {
// Note: this primitive different semantics than its predecessor, stack:optApply
ControlLibrary.NS_2013_03 + "option-apply"};
public String[] getIdentifiers() {
return IDENTIFIERS;
}
public OptionApply() throws RippleException {
super();
}
public Parameter[] getParameters() {
return new Parameter[]{
new Parameter("p", "the program to be executed", true)};
}
public String getComment() {
return "p => p? -- optionally execute the program p";
}
public void apply(final RippleList arg,
final Sink<RippleList> solutions,
final ModelConnection mc) throws RippleException {
RippleList stack = arg;
RippleValue first = stack.getFirst();
final RippleList rest = stack.getRest();
Sink<Operator> opSink = new Sink<Operator>() {
public void put(final Operator op) throws RippleException {
solutions.put(rest.push(
new StackMappingWrapper(new OptionalQuantifier(op), mc)));
}
};
Operator.createOperator(first, opSink, mc);
}
}